Hello,
I am trying to reinstall Ubuntu 13.04 on a disk that already has Windows 7, A dual - boot.
But the installer on the ubuntu 13.04 Disk says:
The computer currently has no detected operating system. What would you like to do? If I install the Ubuntu, ithe Windows 7 will be wiped out.
Please advise where am I going wrong!

Since the possibility if a failing hard drive has already occurred to you, and since this could be a cause of what you are seeing here, this is what you do in Ubuntu 13.04. Open the Disks application. Highlight the hard drive you want to check in the left pane. Click on the cogwheel icon top-right and select SMART data and tests.

Thank you very much for your reply.
The Windows 7 boots up Ok.
I have to 2 500 Gb hard drives on my computer and on one of the drives I had installed Windows 7 and Ubuntu 13.04.
Now, trying to install the ubuntu again it has installed on the other drive. But I want both the operating systems on the same drive.
The drives are Western Digital so I downloaded a programme from its website to diagnose the hard drives and both are perfect, no faults. I did Smart tests.
I am posting the results of $ sudo fdisk -lu

Please advise.
Thank you again.

Last edited by Narendra on Thu Aug 29, 2013 11:52 am, edited 1 time in total.

Two things. Please edit your post and put code tags around your terminal output in order to restore formatting. At the moment, it's making my eyes swim. Code tags thusly:

[code]
Your terminal output
[/code]

Second thing - have you tried choosing "something else" in the installer and simply telling it to install Ubuntu to sdb16 as the / (root) partition? Assuming, that is, that you want to overwrite the current installation.

Don't do that just yet. I'd like to check your fdisk output, but only after it doesn't give me terminal eye failure!

Much obliged! I help staff another forum and if I had £5 for every time I've edited in code tags....

towy71 wrote:The drive setup looks ok but I'm wondering why Narendra has put to installs of whatever Windows on when one is more than enough lol

There is certainly a sufficiency of ntfs partitions!

@Narendra, I might have missed something, but I can't see anything wrong with your fdisk output - not overlapping partitions, no extended outside the physical limit of the drive - the sort of things that can happen to a partition table and drive an installer crazy. Your out-of-order partitions don't matter.

Simple question, but it needs to be asked. When you say sdb didn't show up under something else, it's worth double-checking this. The something else window is quite small and you have - ahem - a lot of partitions. Are you sure you didn't just need to scroll down a bit? The now-you-see-it-now-you-don't scroll thingy is easily missed in Ubuntu.

I have just read your helpful responses to Narenda, and I harbour suspicions about my HHD, so I tried to find out more from the disk utilty, only to find SMART not enabled. Under Smart Tests I find the line is greyed out. The item is ST3200822AS (3.01), 200GB.

Thank you Towy, Redwillow, David and netz for helping me out.
I use windows for image editting only, for adobe photoshop and elements!

Simple question, but it needs to be asked. When you say sdb didn't show up under something else, it's worth double-checking this. The something else window is quite small and you have - ahem - a lot of partitions. Are you sure you didn't just need to scroll down a bit? The now-you-see-it-now-you-don't scroll thingy is easily missed in Ubuntu.

I am not sure now.But The Ubuntu is installed on the second drive. on the second drive now, I'll check it again when there is trouble again.
Thank you again.